CN109628828A - A kind of low yield strength ratio super thick water power high-strength steel sheet and its manufacturing method - Google Patents

A kind of low yield strength ratio super thick water power high-strength steel sheet and its manufacturing method Download PDF

Info

Publication number
CN109628828A
CN109628828A CN201811608959.8A CN201811608959A CN109628828A CN 109628828 A CN109628828 A CN 109628828A CN 201811608959 A CN201811608959 A CN 201811608959A CN 109628828 A CN109628828 A CN 109628828A
Authority
CN
China
Prior art keywords
steel
temperature
steel sheet
low yield
yield strength
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN201811608959.8A
Other languages
Chinese (zh)
Other versions
CN109628828B (en
Inventor
丁庆丰
许晓红
白云
李经涛
杨宏伟
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Jiangyin Xingcheng Special Steel Works Co Ltd
Original Assignee
Jiangyin Xingcheng Special Steel Works Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Jiangyin Xingcheng Special Steel Works Co Ltd filed Critical Jiangyin Xingcheng Special Steel Works Co Ltd
Priority to CN201811608959.8A priority Critical patent/CN109628828B/en
Publication of CN109628828A publication Critical patent/CN109628828A/en
Application granted granted Critical
Publication of CN109628828B publication Critical patent/CN109628828B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/02Ferrous alloys, e.g. steel alloys containing silicon
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/18Hardening; Quenching with or without subsequent tempering
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0221Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
    • C21D8/0226Hot rolling
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/04Ferrous alloys, e.g. steel alloys containing manganese
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/46Ferrous alloys, e.g. steel alloys containing chromium with nickel with vanadium
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/54Ferrous alloys, e.g. steel alloys containing chromium with nickel with boron
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00Microstructure comprising significant phases
    • C21D2211/002Bainite
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00Microstructure comprising significant phases
    • C21D2211/008Martensite

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Heat Treatment Of Steel (AREA)

Abstract

The present invention relates to a kind of low yield strength ratio super thick water power high-strength steel sheets, chemical component is C:0.03~0.08%, Si:0.05~0.35%, Mn:0.60~1.00%, P≤0.012%, S≤0.005%, Cr:0.50~1.00%, Ni:0.10~0.30%, V:0.12~0.18%, B:0.0010~0.0020% by mass percentage, surplus is Fe and inevitable impurity element, meet: Ceq≤0.42%, Pcm≤0.20%.Process flow: continuous casting → slab heating → controlled rolling → press quenching → flaw detection → tempering.Steel of the present invention is designed using C+Mn+Cr+V ingredient, and ingredient is simpler, and Ceq, Pcm value are lower, and weldability is preferable;Press quenching+offline tempering process is used simultaneously, gives full play to the formation that harden ability element promotes bainite, martensitic structure, shortens time of staying temperature, grain size is inhibited to grow up, while helping to save heating energy consumption, shortens the production cycle.

Description

A kind of low yield strength ratio super thick water power high-strength steel sheet and its manufacturing method
Technical field
The present invention relates to the manufacturing process of special steel material, and in particular to a kind of manufacturer of the water power steel plate of low yield strength ratio Method.
Background technique
China's hydroelectric generation accounts for the second of domestic energy resource structure, and in recent years, hydroelectric generation is to pollute small, sustainable development Etc. advantages be rapidly developed, various large-scale, giant hydropower stations are quickly grown on domestic each great rivers, power station capacity and Head pressure is increasing.Power station penstock, spiral case, bifurcated pipe etc. are growing steel demand, to its intensity, toughness Etc. proposing tightened up requirement.The states such as 600MPa quenched pressure steel pipe of hydropower station steel such as 07MnMoVR, WDL610D2, WDB620 Interior trade mark steel grade causes steel plate thickness to increase because intensity is low, and field condition welding procedure is difficult, has been not suitable for super-huge high water head The requirement in power station, and 800MPa hardness of steel carbon equivalent is high, weldability is poor, and preheating is needed to lead to welding surroundings evil of constructing before weldering It is bad.Pressure steel pipe of hydropower station, which is badly in need of a kind of intensity and weldability, at present has more matched steel grade, solves that its wall thickness is thicker to ask Topic.
The patent document of application number (CN201310269680.2) discloses a kind of 800MPa grades of hydropower station pressure pipeline use High strength steel and its production method, the steel tensile strength are more than 780MPa, the wall thickness of penstock can be thinned significantly, but the steel is adopted Produced with quenching+tempering technique, and be added to expensive alloying elements Mo, Nb etc., carbon equivalent is higher, and weldability is poor, to welding It is more demanding, and process flow is long, production cost is higher.
The patent document of application number (CN201510188306.9) discloses a kind of 620MPa grades of hydroelectric project heat of surrender Rolled steel plate and its production method are produced by two stages controlled rolling and controlled cooling add-back fire process, and tensile strength is more than 700MPa, but It is only 40mm thick steel plate that it, which uses 300mm thick stock material production actual (real) thickness, is not belonging to ultra-thick steel plates, and noble element Ni content reaches It is more than 0.04% to 0.35%, Nb content, production cost is higher.
The patent document of application number (CN103045965A) discloses 600MPa grades of hydroelectric penstock steel plates, utilizes 250mm thickness slab is rolled into the steel plate that thickness is no more than 80mm by TMCP technique, and then tempering obtains -20 DEG C of impact flexibility Excellent hydroelectric penstock steel plate.But its intensity is lower, using necessarily wall thickness being caused to increase in giant hydropower station, gives Welding creates great difficulties.
In conclusion there are yield tensile ratio height, weldability for existing pressure steel pipe of hydropower station steel plate and same level ultra-thick steel plates Poor, the problems such as process flow is long, high production cost, brings larger tired to giant hydropower station making in site, construction, welding etc. Difficulty is unable to satisfy the requirement of newly-built large size, giant hydropower station.
Summary of the invention
The purpose of the present invention is providing a kind of inexpensive, low yield strength ratio super thick water power high strength steel for the prior art, adopt With the high Cr high V of the low manganese of low-carbon and it is aided with component system and the press quenching+offline tempering process production of B, Ni microalloying, finished product With a thickness of 80~150mm, steel plate has high intensity, low yield strength ratio, excellent low temperature toughness, low-carbon-equivalent, superior weldability energy etc. Feature, and the technological process of production is short, production energy consumption is low, suitable for mass production.
The present invention solves the above problems used technical solution are as follows: a kind of low yield strength ratio super thick water power high-strength steel sheet, Chemical component be by mass percentage C:0.03~0.08%, Si:0.05~0.35%, Mn:0.60~1.00%, P≤ 0.012%, S≤0.005%, Cr:0.50~1.00%, Ni:0.10~0.30%, V:0.12~0.18%, B:0.0010~ 0.0020%, surplus is Fe and inevitable impurity element.And meet:
Ceq=C+Si/24+Mn/6+Cr/5+Mo/4+V/14≤0.42%,
Pcm=C+Si/30+ (Mn+Cu+Cr)/20+Ni/60+Mo/15+V/10+5B≤0.20%.
The mechanical performance of the water power steel sheet product of the application 80~150mm thickness meets: yield strength ReL>=560MPa, tension Intensity Rm>=700MPa, elongation percentage A >=18%, yield tensile ratio≤0.83, -20 DEG C of KV of side knock function2≥60J;5% strain-aging - 20 DEG C of KV of ballistic work2≥47J.Metallographic structure at 1/4, predominantly bainite+ferrite.
Production purpose to realize the present invention makes super thick power station high strength steel plate meet low yield strength ratio, superior low temperature tough Property, low-carbon-equivalent, superior weldability can etc. characteristics, the restriction reason of the elements such as C, Si, Mn, P, S, Cr, Ni, V, B in the present invention It is described below:
Carbon: excessive C will reduce the low-temperature flexibility of steel plate, deteriorate its weldability, but it can significantly improve armor plate strength.Carbon Content is lower, and the low-temperature flexibility of steel is better.Lower carbon content can promote during the rolling process austenite be formed about it is more " carbon-free area " promotes austenite to the bainite transformation containing high density dislocation, further increases the low-temperature flexibility of steel.C's contains Amount is 0.03~0.08%.
Manganese: mentioning Mn drop C is to improve armor plate strength, improve the important means of its low-temperature flexibility, but Mn too high levels, will be significant Center segregation of casting blank is aggravated, steel plate low-temperature flexibility is influenced, while significantly improving the carbon equivalent of steel and deteriorating its weldability.Mn's contains Amount is 0.60%~1.00%.
P and s: P, S are inevitable impurity element, have shadow to the mouldability, corrosivity, low-temperature flexibility of steel plate It rings, the lower content the better, content≤0.005% of content≤0.012%, S of P.
Chromium: Cr can significantly improve the harden ability of steel and play the role of post-curing, make hardened steel after tempering and have and is excellent Comprehensive performance and stable temper resistance.Excessive Cr will reduce the plasticity of steel, reduce the elongation and section shrinkage of steel Rate.The content of Cr is 0.50~1.00%.
Nickel: Ni can reduce the low temperature ductile-brittle transition temperature of steel, improve the low-temperature flexibility of steel, but the excessive Ni that is added can make cost Increase, the content of Ni is 0.10~0.30%.
Vanadium: V forms V (C, N) compound in conjunction with C, N, reduces the free nitrogen content in steel, improves the strain-aging of steel Energy.V (C, N) austenite grain boundary ferrite Precipitation inhibits the recrystallization of austenite during the rolling process and organizes crystal grain long Greatly, so that fining ferrite grains, improve the intensity and toughness of steel.In high tempering, V (C, N) disperse educt can be risen To precipitation enhancement, the intensity and toughness of steel are further increased.The content of V is 0.12~0.18%.
Boron: micro B element is remarkably improved the harden ability of steel plate, and for quenching state thick steel plate, the addition of B can obviously promote It is formed into martensite or bainite, to improve its intensity.But excessive B austenite grain boundary can be precipitated and generate hot-short in steel Phenomenon.The content of B is 0.0010~0.0020%.
The technological process of production (by taking continuous casting billet as an example) of the low yield strength ratio super thick water power high-strength steel sheet of the application: blast furnace iron Water → molten iron KR processing → 150t oxygen coverter smelting → LF ladle furnace refining → RH vacuum drying oven processing → continuous casting → slab heating → controlled rolling → press quenching → flaw detection → tempering → inspection;
Main technologic parameters are as follows:
1) it smelts: it is blast-melted to be smelted through KR desulfurization, then through oxygen coverter, it controls [P]≤0.010%, [C]≤ 0.04%.In ladle furnace refining processing, and the alloys such as ferrochrome, vanadium iron, ferronickel, manganese iron are added simultaneously, by composition adjustment to target Value, simultaneously [S]≤0.004%.It is refined again in RH vacuum drying oven, adds ferro-boron after being vacuum-treated 1 circulation.
2) continuous casting: using matched pulling rate and temperature, is existed using the production thickness such as whole process protection casting, electromagnetic agitating technology The slab of 450mm and the above specification, casting blank stacking slow cooling 48 hours, slab temperature was transferred to subsequent processing lower than 300 DEG C.
3) it rolls: slab being heated to 1170~1250 DEG C, time inside furnace is 0.6~1.2min/mm × plate thickness mm, is come out of the stove Oxidized iron sheets on surface of casting blank is eliminated by (de-scaling) using high pressure water afterwards;Using two stage controlled rolling: control I-stage finish to gauge temperature Degree is at 970~1010 DEG C, preceding 3 reductions in pass >=35mm;Controlling II stage start rolling temperature is≤930 DEG C, finishing temperature 900 It~920 DEG C, controls last reduction in pass and is no more than 5mm, do not water when two passes after control, keep steel plate flatness, roll 80~150mm thick steel plate is made.
4) press quenching: carrying out temperature correction immediately after stage finish to gauge, steel billet temperature is controlled at 890~910 DEG C after temperature correction, Higher than the Ac3 point of steel plate, press quenching is carried out to lower temperature to 80~150mm thick steel plate, steel plate final cooling temperature is controlled and does not surpass 60 DEG C are crossed, promotes formation bainite in quenching process, form bainite at the hard phase constitution of martensite, especially 1/4 plate thickness, then It detects a flaw, guarantees to be transferred to subsequent processing without steel plate after inherent quality problem.
5) it is tempered: the thickness super thick power station 80~150mm being tempered offline with high-strength steel sheet, comes out of the stove and is air-cooled to room temperature Become finished steel plate afterwards, is arranged 500~580 DEG C of tempering temperature, time inside furnace is 240~450min.
The present invention is using the low Mn high Cr high V ingredient design of low C, press quenching+offline tempering process production.It is used when smelting The pure molten steel of multiple means such as uses self-produced molten steel and low-sulfur steel scrap, strict control harmful element and impurity content, and tight Lattice control [P]≤0.010%;When refining, using desulfurizing agent further deep desulfurization, control [S]≤0.003%;It is closed using Si-Mn Golden deoxidation, strict control Als content reduce molten steel Al2O3Harmful field trash is formed, molten steel again after being vacuum-treated [O]≤ 10ppm,[N]≤35ppm,[H]≤1ppm.Molten steel sublimate can obviously improve steel plate low-temperature flexibility.When press quenching, sufficiently protect The matching such as steel billet temperature, cooling velocity is demonstrate,proved, promotes bainite, martensite etc. in steel using elements such as Cr, the B for improving steel hardenability Hard phase constitution is formed, and the finishing temperature of steel is properly increased, and guarantees that steel billet temperature is higher than its Ac3 point when press quenching, makes super thick A certain amount of bainite is formed at steel plate plate thickness 1/4, then after high tempering, further improve the low-temperature flexibility of steel, while sufficiently Intensity declines to a great extent caused by being weakened using the dispersion-strengthened action of V (C, N) because of factors such as dislocation density reductions, has steel plate still There are higher intensity and excellent low-temperature flexibility;Two passages forbid control to water after finish to gauge simultaneously, avoid causing steel plate because of watering Non-uniform temperature, it is uneven so as to cause steel plate tissue and performance when press quenching.Last reduction in pass≤5mm, can protect Demonstrate,prove the straight degree of steel plate template peace.
Compared with existing production technology and patent, steel of the present invention is designed using C+Mn+Cr+V ingredient, and ingredient is simpler, Ceq, Pcm value are lower, and weldability is preferable;Press quenching+offline tempering process is used simultaneously, gives full play to the promotion of harden ability element Time of staying temperature is shortened in the formation of bainite, martensitic structure, and grain size is inhibited to grow up, while helping to save heating energy consumption, contracting Short production cycle.
The present invention 80~150mm thickness low yield strength ratio super thick water power high-strength steel, performance meet yield strength ReL>=560MPa resists Tensile strength Rm>=700MPa, elongation percentage A >=18%, yield tensile ratio≤0.83, -20 DEG C of KV of side knock function2≥60J;When 5% strain Imitate -20 DEG C of KV of ballistic work2≥47J.Have the characteristics that lower yield tensile ratio, the matching of preferable obdurability, solderability.
Detailed description of the invention
Fig. 1 is metallographic structure, predominantly bainite+ferrite at the 80mm thick steel plate 1/4 of embodiment 2;
Fig. 2 is metallographic structure, predominantly bainite+ferrite at the 150mm thick steel plate 1/4 of embodiment 2.
Specific embodiment
Below in conjunction with multiple groups embodiment, present invention is further described in detail.
The melting chemical composition of various embodiments of the present invention and comparative example is shown in Table 1 (wt%), remaining as Fe and inevitably Impurity element.
Table 1
Above-described embodiment in 150t converter smelting, go back through KR desulfurization, then through the desulfurization of ladle furnace depth and refining treatment by molten iron It is de-gassed in vacuum drying oven, then through slighter compress, electromagnetic agitation and total process protective casting at 450mm thickness slab.
450mm thickness slab is heated to 1180~1240 DEG C, time inside furnace is 0.8~1.2min/mm × plate thickness (mm), out Through high-pressure water descaling after furnace, oxidized iron sheets on surface of casting blank is eliminated;Then controlled rolling, finishing temperature control at 970~1010 DEG C, 35~40mm of preceding 3 reduction in pass controls last reduction in pass and is no more than 5mm, do not water when two passes after control;Finish to gauge Temperature is 900~920 DEG C, after press quenching, and test steel billet temperature is below 60 DEG C, is rolled into 80~150mm thickness finished steel plate; 500~580 DEG C of temperings are carried out again, and time inside furnace is 240~420min, is air-cooled to room temperature after coming out of the stove.
Table 2 mainly rolls for each embodiment and tempering process parameters.
Table 2
Steel plate after tempering heat treatment, laterally tensile sample, impact specimen are processed into sampling at plate thickness 1/4, and surface layer takes Sample processes strain-aging and impacts impact specimen, and carries out Mechanics Performance Testing, the results are shown in Table 3.
3 embodiment base material mechanical property result of table
Seen from table 3, test of embodiment of the present invention steel plate meets yield strength ReL>=560MPa, tensile strength Rm≥ 700MPa, elongation percentage A >=18%, yield tensile ratio≤0.83, -20 DEG C of KV of side knock function2≥60J;5% strain-aging ballistic work- 20℃KV2>=47J, and intensity, elongation percentage, impact flexibility surplus are larger, yield tensile ratio is relatively low, especially at plate thickness 1/4 Excellent in low temperature toughness.
Indicated above, hardness of steel of the present invention is more than 700MPa, practical to bend with excellent obdurability matching and low-temperature flexibility Strong ratio is no more than 0.80;And carbon equivalent Ceq and Pcm value is lower, illustrates it with preferable weldability;In addition steel production control System is simple, and process flow is short, and production cost is low, has a vast market foreground.
Fig. 1 show organization chart of the 80mm thick steel plate at 1/4 thickness in embodiment 2, organizes as bainite+iron element Body.Fig. 2 show organization chart of the 150mm thick steel plate at 1/4 thickness in embodiment 2, organizes as bainite+ferrite. The Organization Matching makes steel have preferable obdurability, while steel also being made to have lower yield tensile ratio.
Steel process flow of the present invention is simple, strong operability and cost is relatively low, Thick Plate Plant can implement in the steel industry.This Invention steel is widely used, can be applied to the industries such as water power, building, bridge, engineering machinery, large-scale, super-huge more suitable for building Power station penstock, spiral case, bifurcated pipe and base etc..
In addition to the implementation, all to use equivalent transformation or equivalent replacement the invention also includes there is an other embodiments The technical solution that mode is formed should all be fallen within the scope of the hereto appended claims.

Claims (9)

1. a kind of low yield strength ratio super thick water power high-strength steel sheet, it is characterised in that: chemical component is C by mass percentage: 0.03~0.08%, Si:0.05~0.35%, Mn:0.60~1.00%, P≤0.012%, S≤0.005%, Cr:0.50~ 1.00%, Ni:0.10~0.30%, V:0.12~0.18%, B:0.0010~0.0020%, surplus is for Fe and inevitably Impurity element meets simultaneously:
Ceq=C+Si/24+Mn/6+Cr/5+Mo/4+V/14≤0.42%,
Pcm=C+Si/30+ (Mn+Cu+Cr)/20+Ni/60+Mo/15+V/10+5B≤0.20%.
2. low yield strength ratio super thick water power high-strength steel sheet according to claim 1, it is characterised in that: 80~150mm thickness The mechanical performance of the steel sheet product meets: yield strength ReL>=560MPa, tensile strength Rm>=700MPa, elongation percentage A >=18%, Yield tensile ratio≤0.83, -20 DEG C of KV of side knock function2≥60J;5% -20 DEG C of KV of strain-aging ballistic work2≥47J。
3. a kind of manufacturing method of low yield strength ratio super thick water power high-strength steel sheet, it is characterised in that: including
(1) it produces blank: by the pouring molten steel for meeting ingredient design at continuous casting billet, or pouring into steel ingot, then steel ingot cogging is obtained Obtain blank;
(2) roll: heating blank makes complete austenitizing, then uses two stage controlled rolling: control I-stage finishing temperature At 970~1010 DEG C, preceding 3 reductions in pass >=35mm;Control II stage start rolling temperature be≤930 DEG C, finishing temperature be 900~ It 920 DEG C, controls last reduction in pass and is no more than 5mm, do not water when two passes after control, keep steel plate flatness, rolling At 80~150mm thick steel plate;
(3) press quenching: carrying out temperature correction immediately after II stage finish to gauge, steel billet temperature is controlled at 890~910 DEG C after temperature correction, Higher than the Ac3 point of steel plate, press quenching is carried out to lower temperature to 80~150mm thick steel plate, steel plate final cooling temperature is controlled and does not surpass 60 DEG C are crossed, promotes formation bainite in quenching process, form bainite at the hard phase constitution of martensite, especially 1/4 plate thickness, then It detects a flaw, guarantees to be transferred to subsequent processing without steel plate after inherent quality problem;
(4) it is tempered: the thickness super thick power station 80~150mm being tempered offline with high-strength steel sheet, is come out of the stove after being air-cooled to room temperature As finished steel plate.
4. the manufacturing method of low yield strength ratio super thick water power high-strength steel sheet according to claim 3, it is characterised in that: step (1) smelting molten steel: it is blast-melted to be smelted through KR desulfurization, then through oxygen coverter, it controls [P]≤0.010%, [C]≤ 0.04%.In ladle furnace refining processing, and the alloys such as ferrochrome, vanadium iron, ferronickel, manganese iron are added simultaneously, by composition adjustment to target Value simultaneously [S]≤0.004%, then is refined in RH vacuum drying oven, adds ferro-boron after being vacuum-treated 1 circulation.
5. the manufacturing method of low yield strength ratio super thick water power high-strength steel sheet according to claim 3, it is characterised in that: step (1) acquisition of continuous casting billet: using matched pulling rate and temperature, pours into thickness using whole process protection casting, electromagnetic agitating technology In 450mm and the slab of the above specification, casting blank stacking slow cooling 48 hours or more, slab temperature was transferred to subsequent processing lower than 300 DEG C.
6. the manufacturing method of low yield strength ratio super thick water power high-strength steel sheet according to claim 3, it is characterised in that: step (2) in rolling process, before the rolling by heating of plate blank to 1170~1250 DEG C, time inside furnace is 0.6~1.2min/mm × plate thickness Mm is eliminated oxidized iron sheets on surface of casting blank using high pressure water after coming out of the stove.
7. the manufacturing method of low yield strength ratio super thick water power high-strength steel sheet according to claim 3, it is characterised in that: step (4) in tempering process, it is arranged 500~580 DEG C of tempering temperature, time inside furnace is 240~450min.
8. the manufacturing method of low yield strength ratio super thick water power high-strength steel sheet according to claim 4, it is characterised in that: molten steel Target component, wt%:C:0.03~0.08%, Si:0.05~0.35%, Mn:0.60~1.00%, P≤0.012%, S≤ 0.005%, Cr:0.50~1.00%, Ni:0.10~0.30%, V:0.12~0.18%, B:0.0010~0.0020%, it is remaining Amount is Fe and inevitable impurity element, is met simultaneously:
Ceq=C+Si/24+Mn/6+Cr/5+Mo/4+V/14≤0.42%,
Pcm=C+Si/30+ (Mn+Cu+Cr)/20+Ni/60+Mo/15+V/10+5B≤0.20%.
9. the manufacturing method of low yield strength ratio super thick water power high-strength steel sheet according to claim 3, it is characterised in that: give birth to Metallographic structure of the product of production at 1/4 thickness is mainly bainite+ferrite.
CN201811608959.8A 2018-12-27 2018-12-27 Low-yield-ratio ultra-thick hydroelectric high-strength steel plate and manufacturing method thereof Active CN109628828B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201811608959.8A CN109628828B (en) 2018-12-27 2018-12-27 Low-yield-ratio ultra-thick hydroelectric high-strength steel plate and manufacturing method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201811608959.8A CN109628828B (en) 2018-12-27 2018-12-27 Low-yield-ratio ultra-thick hydroelectric high-strength steel plate and manufacturing method thereof

Publications (2)

Publication Number Publication Date
CN109628828A true CN109628828A (en) 2019-04-16
CN109628828B CN109628828B (en) 2020-11-20

Family

ID=66078159

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201811608959.8A Active CN109628828B (en) 2018-12-27 2018-12-27 Low-yield-ratio ultra-thick hydroelectric high-strength steel plate and manufacturing method thereof

Country Status (1)

Country Link
CN (1) CN109628828B (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111020349A (en) * 2019-10-18 2020-04-17 江阴兴澄特种钢铁有限公司 Manufacturing method of 150-doped 200 mm-thick normalized easy-to-weld hydroelectric steel plate
CN111763880A (en) * 2020-06-16 2020-10-13 九江萍钢钢铁有限公司 Low-yield-ratio ultra-thick hydroelectric high-strength steel plate and manufacturing method thereof
CN113355600A (en) * 2021-05-30 2021-09-07 五矿营口中板有限责任公司 Super-thick steel plate for online quenching 800 MPa-grade engineering machinery and manufacturing method thereof
CN114395691A (en) * 2021-12-16 2022-04-26 南阳汉冶特钢有限公司 Production method of low-welding-crack-sensitivity crack arrest steel SX780CF for hydroelectric engineering
CN115505821A (en) * 2022-09-20 2022-12-23 苏州雷格姆海洋石油设备科技有限公司 Preparation method of high-performance bainite steel connecting piece material for vertical connecting module of deep sea underwater umbilical cable

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101497967A (en) * 2008-01-31 2009-08-05 株式会社神户制钢所 High tension steel plate with excellent weldability
CN106319376A (en) * 2015-06-29 2017-01-11 鞍钢股份有限公司 Novel low-weld-crack-sensitivity high-strength steel plate

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101497967A (en) * 2008-01-31 2009-08-05 株式会社神户制钢所 High tension steel plate with excellent weldability
CN106319376A (en) * 2015-06-29 2017-01-11 鞍钢股份有限公司 Novel low-weld-crack-sensitivity high-strength steel plate

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111020349A (en) * 2019-10-18 2020-04-17 江阴兴澄特种钢铁有限公司 Manufacturing method of 150-doped 200 mm-thick normalized easy-to-weld hydroelectric steel plate
CN111763880A (en) * 2020-06-16 2020-10-13 九江萍钢钢铁有限公司 Low-yield-ratio ultra-thick hydroelectric high-strength steel plate and manufacturing method thereof
CN113355600A (en) * 2021-05-30 2021-09-07 五矿营口中板有限责任公司 Super-thick steel plate for online quenching 800 MPa-grade engineering machinery and manufacturing method thereof
CN113355600B (en) * 2021-05-30 2022-10-25 日钢营口中板有限公司 Super-thick steel plate for online quenching 800 MPa-grade engineering machinery and manufacturing method thereof
CN114395691A (en) * 2021-12-16 2022-04-26 南阳汉冶特钢有限公司 Production method of low-welding-crack-sensitivity crack arrest steel SX780CF for hydroelectric engineering
CN115505821A (en) * 2022-09-20 2022-12-23 苏州雷格姆海洋石油设备科技有限公司 Preparation method of high-performance bainite steel connecting piece material for vertical connecting module of deep sea underwater umbilical cable

Also Published As

Publication number Publication date
CN109628828B (en) 2020-11-20

Similar Documents

Publication Publication Date Title
CN104513936B (en) A kind of yield strength 1100MPa grades of quenching and tempering, highs and its production method
WO2016095721A1 (en) Quenched-tempered high-strength steel with yield strength of 900 mpa to 1000 mpa grade, and manufacturing method therefor
JP6466582B2 (en) Yield strength 800 MPa class high strength steel and method for producing the same
CN107475620B (en) Low-temperature pressure container quenching and tempering type A537Cl2 steel plate and its production method
US11053563B2 (en) X80 pipeline steel with good strain-aging performance, pipeline tube and method for producing same
CN109628828A (en) A kind of low yield strength ratio super thick water power high-strength steel sheet and its manufacturing method
CN104532156B (en) A kind of yield strength 1300MPa grades of quenching and tempering, highs and its production method
CN104357742B (en) 420MPa high-thickness hot-rolled steel sheet for ocean engineering and production method thereof
CN110438414A (en) A method of eliminating ultra-wide ferritic stainless steel surface crack of plate
CN101928876B (en) TRIP/TWIP high strength plastic automotive steel with excellent processability and preparation method thereof
CN108070779A (en) A kind of solderable fine grain, high strength degree structural steel and iron and its production method
CN107338393A (en) A kind of yield strength is more than 1400MPa ultra-high strength steel plates and its production method
CN108315671B (en) 1000MPa grades of low yield strength ratio super-high strength steels of yield strength and preparation method thereof
CN104911503A (en) Extra-thick tempering EH40 steel for ocean engineering and preparation method thereof
CN110499474A (en) High temperature resistant 400HB wear-resisting steel plate and its production method
CN108624744A (en) A kind of Q500qE bridge steel plates and its production method
CN109338215A (en) One kind 8~25mm thickness low yield strength ratio tank car high strength steel plate and its manufacturing method
CN104561827A (en) High strength steel with yield strength to be 900-1000MPa grade and production method of high strength steel
CN107937807A (en) 770MPa grades of low-welding crack-sensitive pressure vessel steels and its manufacture method
CN107881415B (en) A kind of high temperature wear resistant steel plate and its manufacturing method
CN112501496A (en) On-line quenching type double-phase low-yield-ratio steel plate and production method thereof
CN109609729A (en) A kind of yield strength 650MPa grades of stainless steel plates and manufacturing method
CN108368593A (en) High strength steel and its manufacturing method with excellent low temperature strain-aging impact characteristics
CN110358970B (en) Welded structure bainite high-strength steel with yield strength of 1100MPa and preparation method thereof
CN102191430A (en) Easy welding steel plate with yield strength of 550MPa and high toughness and manufacturing method thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant